In the late 1980s, pianist Rodney Sauer was rummaging through sheet music at the University of Colorado at Boulder, where he was working toward a doctorate in chemistry, looking for foxtrots and tangos to play with his 1920s dance band, his real passion.

By chance he came across a sheaf of photoplay music - mood-evoking pieces composed for silent movies that were patched together and played by musicians in movie theaters across America to accompany whatever film was flickering on the screen that week. Intrigued, Sauer photocopied some of the music and began playing it with what became the Mont Alto Motion Picture Orchestra, the noted Colorado chamber quintet that has stitched together and performed dozen of silent-movie scores that it performs at festivals across the country and for DVD releases of silent classics like 1927's Cecil B. DeMille-produced "Chicago."

Sauer, a Berkeley native who finished his master's degree in chemistry but left science for music, doesn't aim to exactly replicate the music that originally accompanied these films, which would have sounded different depending on whether you saw them in a movie palace with an 80-piece orchestra, a theater with a house quintet or a small cinema with an improvising organist or player piano.

"We're saying this is what you might've heard in a good movie theater in the 1920s," says Sauer, 50, whose ensemble will perform its scores to three Alfred Hitchcock silent movies - "Blackmail," "The Ring" and "The Lodger" - at the Castro Theater next week as part of the San Francisco Silent Film Festival's Hitchcock 9 mini-fest. With most silent movies, he adds, "there was no one score."

Sauer draws on about 5,000 pieces from various collections, including popular tunes of the day and music by silent-movie composers like J.S. Zamecnik, an American who studied with Dvorák in Prague, and the Frenchman Gaston Borch, a student of Jules Massenet's, whose pieces were sold in photoplay music catalogs. Sauer weaves 40 to 80 pieces into a score.

"I'm a compiler. It's not a glamorous term, but it's accurate," says Sauer, whose group shares the Castro bill with other superior silent-movie musicians such as composer DonaldSosin and Stephen Horne, an Englishman who improvises at the piano as the film unfolds.

Sauer improvises a tad when needed to let the music breathe, but the band plays the music as written, sometimes playing generic photoplay music with titles like "Hurry" and "Dramatic Tension." He's particularly fond of a Gaston piece called "The Slimy Viper," perfect for a villain with a twisty mustache.

Compiling each score, "I try to support each scene emotionally with music while also keeping in mind the entire arc of the film," Sauer says. " 'The Ring' for instance, has some very tense emotional scenes. In the guy's private moments he's jealous. But in his public life, he's having great success as a boxer. So I have to remember to put in some perky music when things are going well. We don't want to be wallowing in melodrama the whole time. We want to shape the score so it rise and falls with the film."

Piano and more

Alan Broadbent, the pianist who played on and arranged those primo Charlie Haden Quartet West records and won a Grammy for arranging Natalie Cole's version of "When I Fall in Love," plays an intimate solo date Saturday at Piedmont Piano Company in Oakland's Uptown. (The venerable shop left Piedmont in 2010 for its art deco digs.)

In other concerts, flugelhornist Dmitri Matheny and his band appear June 16, and singer Madeline Eastman,pianist Randy Porter, drummer Allison Miller and the best-named bass player in jazz, Ratzo Harris play July 1.

BBB got talent

This year's stars of the future were crowned Monday night as the Bay Area high school winners of the Steve Silver Foundation & "Beach Blanket Babylon" Scholarship for the Arts. The three who received $10,000 toward their college education are Riley O'Flynn, from Ruth Asawa San Francisco School of the Arts, for dance, Madeline Rouverol, from Santa Rosa High School, for acting, and Kristina Dizon, from Rocklin High School, for voice. For more information on the scholarship program visit www.beachblanketbabylon.com/scholarship

Glorious guitars

Composer Rhys Chatham, whose major work for 100 electric guitars, "A Secret Rose," will be presented by San Francisco's Other Minds in the fall, will be in town to stir things up Friday at the Lab, where four guitarists serve up his "Guitar Trio" (Ava Mendoza, JohnSchott, George Chen and John Krausbauer) accompanied by bassist Lisa Mezzacappa and drummer Jordan Glenn, and Saturday talking with Other Minds' artistic director Charles Amirkhanian at an "exclusive" event in some artist's Mission District studio. Even we don't know where it is.